using System;

namespace Org.BouncyCastle.Asn1.X509
{
	public class PolicyInformation
		: Asn1Encodable
	{
		private readonly DerObjectIdentifier	policyIdentifier;
		private readonly Asn1Sequence			policyQualifiers;

		private PolicyInformation(
			Asn1Sequence seq)
		{
			if (seq.Count < 1 || seq.Count > 2)
			{
				throw new ArgumentException("Bad sequence size: " + seq.Count);
			}

			policyIdentifier = DerObjectIdentifier.GetInstance(seq[0]);

			if (seq.Count > 1)
			{
				policyQualifiers = Asn1Sequence.GetInstance(seq[1]);
			}
		}

		public PolicyInformation(
			DerObjectIdentifier policyIdentifier)
		{
			this.policyIdentifier = policyIdentifier;
		}

		public PolicyInformation(
			DerObjectIdentifier	policyIdentifier,
			Asn1Sequence		policyQualifiers)
		{
			this.policyIdentifier = policyIdentifier;
			this.policyQualifiers = policyQualifiers;
		}

		public static PolicyInformation GetInstance(
			object obj)
		{
			if (obj == null || obj is PolicyInformation)
			{
				return (PolicyInformation) obj;
			}

			return new PolicyInformation(Asn1Sequence.GetInstance(obj));
		}

		public DerObjectIdentifier PolicyIdentifier
		{
			get { return policyIdentifier; }
		}

		public Asn1Sequence PolicyQualifiers
		{
			get { return policyQualifiers; }
		}

		/*
		 * PolicyInformation ::= Sequence {
		 *      policyIdentifier   CertPolicyId,
		 *      policyQualifiers   Sequence SIZE (1..MAX) OF
		 *              PolicyQualifierInfo OPTIONAL }
		 */
		public override Asn1Object ToAsn1Object()
		{
			Asn1EncodableVector v = new Asn1EncodableVector(policyIdentifier);

			if (policyQualifiers != null)
			{
				v.Add(policyQualifiers);
			}

			return new DerSequence(v);
		}
	}
}
